Ignition system for internal-combustion engines



A. H. 'MIDGLEY. IGNITION SYSTEM FOR INTERNAL COMBUSTION ENGINES.

APPL'ICATION men FEB. a. 1919.

1,351,396. Patented Aug. 31, 1920.

INVENTOR BY I AVA/waf le;

ATTORNEY ALBERT" HENRY MIDGLEY, or ACTON VALE,- extensive,

ASSIGNOR or ONEQHALF To C. A. VANDERVELL & COMPANY LIMITED, 0F ACTON VALE, ENG-LAND,

IGNITION SYSTEM FOR. INTERNAL-COMBUSTION ENGINES.-

Application filed February 6, 1919.

Y '0 all whom it may concern lie it known that I, ALBERT HENRY MinoLnY, a subject of the King of Great Britain and Ireland, and residing at Warple \Vay, Acton Vale, in the county of Middlesex, England, have invented certain new and useful Improvements in and Relating to Ignition Systems for Internal-Combustion Engines, of which the following is a specification.

This invention relates to an improved ignition system for internal combustion engines of the kind in which a dynamo arranged in parallel with a battery of accumulators is connected to the ignition coil, or coils, the battery being more particularly intended to supply current to the'latter at "starting and the dynamo to supply the current to such coil or coils ai'ter the engine has started to rotate under its own power.

. The main object of the invention is to pro vide improved means of connections so as to reduce the amount of wiring and thereby the weight of the whole system, which is of special importance in connection with air craft, another object being. to insure the working of the ignition circuit whenlone or molb of the connections are broken.

According to the present invention the ignition coil with its circuit breaker, the dynamo and the battery are star and delta connected, that is-to say they are connected at one end to a common pointqvhile their other ends are interconnected as in the well-known delta connection, preferably through earth connections, and the part of the star connection which-includes the battery also includes a switch which is interposed between the battery and a connecting wire coming from the common point of the star connection and is adapted in one position to connect the bat tery to the dynamo and ignition coil and in the other position to disconnect it therefrom and short-circuit both the dynamo and the' ignition coil.

W Vith this arrangement the size of the wire between the, switch and the ignition unit 1s small as it only carries the difference be-- tween the ignition current and the dynamo current.

The invention also consists in arranging that the short-circuiting connection effected by the switch shall also effect the short-circuit of the shunt winding of the dynamo when the automatic cut-out is open. In or- Specification of Letters Patent.

and earthed Patented Aug. 31, 1920. Serial No. 275,360. i

(101' to effect this, the automatic cut-out'is inserted in the connection between the one brush of the dynamo and the common point of the star connection, while one end of the shunt winding is, connected to the said common point and its other end to the same point as the other brush of the dynamo, preferably the earth.

Referring to the accompanying drawing wvhich illustrates the invention diagrammatically and by way of example, a, a are two distributers associated with two banks of cylinders, 6 c the primary and secondary coil of the ignition coil. and (Z 6 the cam make and break of the circuit breaker associated with one bank of cylinders, and If, a the primary and secondary coil of the ignition coil and d e thee-am and earthed make and break of the circuit breaker associated with the other bank of cylinders.

The dynamo 7", one brush g of which is earthed while its other'brush gis connected to the ignition system by a connecting wire it, is provided with a shunt winding 2', one end of which is earthed while its other end is connected to the point of connecton j between the dynamo and the ignition system,

the automatic cut-out la being'insert'ed between the brush g and the point of connection j.

The connecting wire it between the dynamo and the ignition 'coils is connected to the earthed battery by means of a two-way switch m, which in one position connects both the dynamo and the ignition coils to the battery, and in the other position disconnects the battery and short-circuits, both the d namo and the ignition coils through earth.

.Each of the ignition provided with a trembler a a respectively, which are controlled by the closing of an earthed switch 0 and are operative when the corresponding make and breaks 6 e are open. 1

The ignition coils, automatic cut-out, distributers and dynamo are all mounted to gether in such a manner as to form a com coils is preferably pact unit.

What I claim is 1. An ignition system for internal com bustion engines comprising in the combination of an ignition coil and circuit breaker, with a battery for supplying current to connection between the free ends of such star connection, the part of the star connectionwhich includes the battery also com prising a connecting wire between the common point of the star connection and the -battery, and a switch between the connecting Wire and the battery, said switch having a movable contact arm and two stationary contacts, the movable contact arm being connected to the said connecting wire, and

one of the stationary contacts being connected to the battery, while the second stationary contact of the switch is so connected as to be capable of short-circuiting both the dynamo and the ignition coil with its circuit breaker when the contact arm is in contact therewith, as and for the purpose set forth.

2. An ignition system ror internal combustion engines comprising in the combination of an ignition coil and circuit breaker with a battery for supplying current to said ignition coil at starting and with a dynamo for supplying current to the ignition .coil after the engine has been started, an electrical star connection between the ignition coil menses with its circuit breaker, the dynamo and the battery, the free ends of such star connection being earthed and the part of the star connection which includes the battery also comprising a connecting wire between the common point of the star connection and the battery, and aswitch between the connecting wire and the bartery, said switch having a movable contact arm and two stationary contacts, the movable contact arm being connected to the said connecting wire,'and one of the stationary contacts being connected to the battery, while the second stationary contact of the switch is con nected to earth, as and for the purpose set forth.

3. An ignition system for internal combustion engines as claimed in claim 2, the dynamo of which has a shunt excitation winding connected at the one end to the common point of the star connection and at the other end to earth, and an armature connected at one end to earth and at the other end to an automatic cut-out which is connected to the common point of the electric star connection, as and for the purpose set forth. 7

I n testimony whereof I have signed my name to this specification.

ALBERT HENRY MIDGLEY. 

